skip to main content

DOE PAGESDOE PAGES

Title: Electron-acoustic solitons and double layers in the inner magnetosphere: ELECTRON-ACOUSTIC SOLITONS

The Van Allen Probes observe generally two types of electrostatic solitary waves (ESW) contributing to the broadband electrostatic wave activity in the nightside inner magnetosphere. ESW with symmetric bipolar parallel electric field are electron phase space holes. The nature of ESW with asymmetric bipolar (and almost unipolar) parallel electric field has remained puzzling. To address their nature, we consider a particular event observed by Van Allen Probes to argue that during the broadband wave activity electrons with energy above 200 eV provide the dominant contribution to the total electron density, while the density of cold electrons (below a few eV) is less than a few tenths of the total electron density. We show that velocities of the asymmetric ESW are close to velocity of electron-acoustic waves (existing due to the presence of cold and hot electrons) and follow the Korteweg-de Vries (KdV) dispersion relation derived for the observed plasma conditions (electron energy spectrum is a power law between about 100 eV and 10 keV and Maxwellian above 10 keV). The ESW spatial scales are in general agreement with the KdV theory. We interpret the asymmetric ESW in terms of electron-acoustic solitons and double layers (shocks waves).
Authors:
ORCiD logo [1] ; ORCiD logo [2] ; ORCiD logo [1] ; ORCiD logo [1] ; ORCiD logo [3] ; ORCiD logo [4] ; ORCiD logo [5] ; ORCiD logo [6]
  1. Univ. of California, Berkeley, CA (United States). Space Sciences Lab.
  2. Univ. of California, Berkeley, CA (United States). Space Sciences Lab.; Taras Shevchenko National Univ. of Kiev (Ukraine)
  3. Univ. of California, Los Angeles, CA (United States); Russian Academy of Sciences (RAS), Moscow (Russian Federation)
  4. Univ. of Orleans (France)
  5. Los Alamos National Lab. (LANL), Los Alamos, NM (United States)
  6. Univ. of Iowa, Iowa City, IA (United States)
Publication Date:
Report Number(s):
LA-UR-17-24827
Journal ID: ISSN 0094-8276; TRN: US1702886
Grant/Contract Number:
AC52-06NA25396
Type:
Accepted Manuscript
Journal Name:
Geophysical Research Letters
Additional Journal Information:
Journal Volume: 44; Journal Issue: 10; Journal ID: ISSN 0094-8276
Publisher:
American Geophysical Union
Research Org:
Los Alamos National Lab. (LANL), Los Alamos, NM (United States)
Sponsoring Org:
National Aeronautic and Space Administration (NASA); USDOE
Country of Publication:
United States
Language:
English
Subject:
79 ASTRONOMY AND ASTROPHYSICS; Heliospheric and Magnetospheric Physics
OSTI Identifier:
1402638